#TheDress is black and blue– and the sun is green?

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#TheDress is black and blue– and the sun is green?

(WHNT)– Now that the mystery of #thedress has been solved, how about another color crux?

When I first learned the following fact in my Physical Meteorology class, I knew the day would come where I could prove that the sun was in fact green. Yes, green.

That day has come.

We’ll use Wein’s Law to prove this. Wein’s Law– also known as Wein’s Displacement Law– describes the relationship between the temperature of an object and the peak wavelength of the light it emits.

Not quite as scary as some other meteorological equations we learn.

We know based on Wein’s Law that the wavelength of the sun’s peak light emission is approximately 0.5 micrometers.

When we look at the visible light region of the electromagnetic spectrum, we find that the dominant color between 0.5 and 0.6 micrometers is GREEN!

Note: The temperature of the surface of the sun is not clearly defined– so depending on the approximation you use, your peak wavelength may vary a little.

So why doesn’t it look green? It’s because the sun also emits light at other wavelengths– enough that our eyes blending these wavelengths together perceive the combination as white light.

Many people wonder why the sun looks white when it is high in the sky, but looks red when it is setting or rising. This has to do with Earth’s atmosphere scattering the sun’s light. When rising and setting, the light has to travel through more atmosphere, thus only the longest wavelengths of light (reddish-orange colors) are seen.

When the sun is directly overhead, the shorter waves– primarily blue– bounce off air molecules in the atmosphere and scatter.